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HOMESERVICE MANUALSBUICK1980REGAL BASE, 3.8L ENG VIN AREPAIR AND DIAGNOSISHEATING, VENTILATION & A/C (HVAC)HVAC CONTROL SYSTEMSAUTO. A/C SYSTEMS - TROUBLESHOOTING & DIAGNOSISTEMPERATURE CONTROL PROBLEMSYSTEM OPERATES ONLY AT MAX HEAT
1980 Buick Regal Base, 3.8L Eng VIN A

System Operates Only At Max Heat

1980 Buick Regal Base, 3.8L Eng VIN ASECTION System Operates Only At Max Heat

This is usually an electrical problem. Problems outside the programmer can generally be separated from internal programmer malfunctions as follows:

  1. Set temperature dial to "65" and control lever to "ECONOMY", with system operating.
  2. Observe programmer through slot in lower portion of cover. Programmer should now move to Max A/C position. If so, problem is in one of the following areas:
    • Disconnected or malfunctioning in-car sensor.
    • Open circuit or backed-out terminal in 3-way connector (located under instrument panel on right side near programmer.)
  3. If programmer did not move to Max A/C, problem is in one of the following areas:
    • Disconnected or defective temperature dial.
    • Disconnected or open in ground circuit (black wire) between control head and programmer.
    • Malfunction within programmer assembly.
RENDER: 1.0x

NO RELATED

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